Teaching Modal Verbs

Modal verbs are auxiliary verbs that add meaning to the main verb. They are never used as main verbs. There are nine modal verbs in English: will, would, can, could, shall, should, may, might, and must. Modals use the same sentence structure as other auxiliary verbs to form sentences and questions.

• Sentence Structure = Subject + Modal Auxiliary + Verb  = He can swim.

• Question Structure = Modal Auxiliary + Subject + Verb = Can you swim?

Modal and semi-modal verbs are used to express many different concepts.

• Asking Permission                          Can I go outside?
• Expressing Possibility                     I might buy a new bike.
• Give Advice / Suggestion                You should go to the game.
• Expressing Certainty                       They will come tomorrow.
• Expressing Probability                     It may be sunny.
• Expressing Willingness / Refusal     I could help you.
• Making Requests /Offers                  Would you help me?
• Expressing Obligation/Necessity      You must be on time.
• Expressing Ability                             I can drive a car.

Teaching Modals

Because modal verbs are used in common everyday conversation and written communication, they are taught at all levels of English. At the beginning levels modals are used for communication purposes. Students learn to express ability, state possibility, make requests, and ask for/give permission.

• Ability -        I can play the guitar.
• Possibility -  It might rain tomorrow.
• Requests -   Can you help me?
• Permission - May I go to the park? Yes, you may.

At the intermediate level students learn new modals that can be used to give advice/suggestions and express obligation/necessity.

• Advice -       You could email or text them.
• Obligation -  You should be on time for your appointment.

Also the subtleties of modal meanings are taught at the intermediate level.

• Formal  - Would you please ___?
• Polite    - Could you please ___? 
• Informal - Can you ___?

• 100% - It will rain tomorrow.
•   50% - It may rain tomorrow.
•   10% - It might rain tomorrow.

 At advanced levels student learn how to use past forms and conditional phrases using modals. 

• When I was young I could sprint fast.
• I would have gone to school but I was ill. 

General Rules for Modals

Because a modal verb can have several meanings, their meaning is always determined by the context. So when teaching modal verbs students should be warned about the following: 

1. Do not translate directly. Define the meaning of the modal by the context of the conversation or passage.

2. Do not assign a modal verb one meaning. The modal 'can' is used to express a variety of meanings.

• Ability           I can play the piano.
• Request       Can I go to the watch T.V.?
• Permission  Yes, you can go to the show.
• Possibility    We can win beat this game.

3. Modals are used with the main verb only. Do not add 'to'.

• He can speak four languages.
• NOT - He can to speak four languages.

4. Do not change a modal verb to show third person singular.

• He can swim.   
• NOT - He cans swim.
• She could have read the book before.
• NOT - She could has read it before.

5. Create negative statements by adding 'not' after the modal verb. Use 'could not, may not, might not, should not, will not, must not, will not, and would not'. Exceptions include cannot and semi-modals. Do not add the words 'don't, doesn't, won't, isn't, aren't, wasn't, or weren't'.   

• You should not use a pen.   
• NOT  - You don't should use a pen.

6. Semi-modal verbs include ought to, have to, be able to, need to, going to, supposed to, and had better. These have a different grammar and that must be learned.

We hope these suggestions are helpful for teaching English Learners at all levels about Modal and Semi-modal Verbs.